The two Pokemon looked around.
"We seem to be in a... forest?" Shaymin stated, unsure. Suicune nodded.
"But why?" she asked.

(But Primal's can happen by holding Red/Blue orb, which is essentially the same as a Mega Stone only it auto-starts the transformation)
Rayquaza and Yveltal checked the surroundings "Why are we smaller?" They both asked, Groudon simply shrugged

(He's right.)
Thw two girls wandered around.
"It feels like something is missing." Shaymin said.

(OoC: Hmmm, okay. It will only be as strong as a normal Mega Evolution, though.

Also gonna assume my character is far away from the others.)

Reshiram shook her head. It doesn't matter right now. What she needs to do is find out where she is. Reshiram flew up in the sky to survey the area.

(Okies :3)
Yveltal and Rayquaza attempted to fly upwards to scout out the area whereas Groudon just walked on the ground

Reshiram didn't recognize this place. Where was she, exactly?

"Mhmm, Clouds, Trees, More clouds and trees, Where are we?" Yveltal asked Rayquaza and Groudon
"No clue!" Both replied in the exact same tone.

Reshiram headed off in one direction, if only to find another Pokemon.

Rayquaza and Yveltal landed because they were strangely tired, Groudon simply looked at the two in confusion

She soared through the sky, but her endurance eventually gave out. How? Reshiram had been able to fly further, but she had only flew as far as a normal Pokemon that is capable of flight. She suddenly saw a Pokemon that resembled a Spinarak, but was much thinner and lacked the markings. And it had red eyes, too.

"What the hell, where are our powers?" the 3 pokemon wondered